Process of burning powdered coal and analogous fuel.



E. P. ROBERTS.

PROCESS OF BURNING POWDERED COAL AND ANALOGOUS FUEL.

APPLICATION FILED DEC. Io, 1915.

1,200,028. y Patented OCI-.3,1916.

"MQW 1M v.; W

. F nel.l of which the following is a full, clear,

UNITED sTA'rEsmirENT oEEroE. y

EDWARD P. ROBERTS, or CLEVELAND, omo. l

PROCESS OF BURNING POWDERED COA-L AND ANALOGOUS FUEL.

Application led December 10, 1915.

To all whom t may concern:

' Be it known that I, EDWARD P. ROBERTS, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Processes of BurningPowdered Coal and Analogous and exact description.

This invention has for its special object to practically and efficientlyburn powdered coal in a shorter combustion chamber than is now requiredwhen mechanical baffles. are not used. and under conditions such that` asubstantially complete combustion of the fuel may be effected, and theproduced heat controlled and distributed as required, and the fuelparticles prevented from impinging against the walls or other parts ofthe combustion chamber. It will be apparent, however, that the inventionmay be advantageously employed in the burning of oil or gas, althoughthe beneficial results of so doing may not be relatively as great aswhen powdered coal is used as the fuel.

To these ends the invention consists in the herein described method bywhich to so deflect the flaming stream of air and fuel which is blowninto the combustion chamber in the usual way, that said stream willfollow any desired sinuous path through the combustion chamber withoutallowing the fuel content to contact with the walls thereof, and wherebyalso the originally introduced supply of fuel and air may besupplemented by the introduction of additional airand additional fuel towhat extent may be desirechwwhich invention is hereinafter described anddefinitely set forth in the appended claims. I

In the dra-wing, Figure 1 is a Sectional. side elevation of-a combustionchamber associated with means by which to control in the desired mannerthe burning stream of air and fuel discharged forcefully into the same;Fig. 2 is a sectional plan view of another combustion chamber andassociated means whereby to deflect said burning stream of fuel and airhorizontally from one side of the combustion chamber to the other as ittravels from the inlet to the outlet of said combustion chamber; Fig. 3is a longitudinal sectional view of another combustion chamberassociated with somewhat dierent means for causing the required de-Specification of Letters Patent.

Patented Oct. 3, 1916.

Serial No. 66,028.

flection of the stream of air and fuel which has been blown into saidchamber.

Referring to the parts by reference characters, A represents thecombustion chamber which, as shown in Figs. l and 2, is rectangular',but may have any desired shape. It may be constructed of any suitablelna/terial, and it has at one end the inlet B and at the opposite endthe outlet C. A stream of fuel and air is to beblown through the inletinto the combustion cham- Y ber in the usual Way and by the usual or anysuitable means,-\vhiclrstream will be immediately ignited within thecombustion chamber, and will therefore appear as a long flame therein.The heated products of combustion will leave the combustionchamberthrough the outlet C, and may be led to any desired point of use.l

It will be noted that the combustion chambers shown in Figs. 1 and 2 arewholly unobstructed, 'and that the combustion chamber shown in Fig.contains nothing by which the stream of fuel and air will bemechanically obstructed in its passage from the inlet to the outlet ofsaid combustion chamber. Therefore, except for the supplemental streamsof air, or air and fuel, to be introduced as hereinafter described, theburning main stream of fuel and air blown forcefully into this chamberthrough the inlet would pass directly to and through the outlet.

Referring particularly to Fig. 1, D, E, F and G represent respectivelynozzles whkich pass through the walls of the combustion chamber so thatthey-may discharge air, or air and fuel mixed; and these may be set atany angle tothe flaming main. Stream, such that the supplemental airstreams will intersect said main stream`and deflect it to `the desiredextent and in the desired direction. The number and capacity of thesenozzles, and the position in which they are placed, will depend uponwhat particular results one desires to obtain by means of the streams ofair or air and fuel discharged through them into the combustion chamber.In this figure the nozzle D is directed downward through the top wall ofthe combustion chamber; the nozzle E is directed'horizontally throughthe end wall near the bottom of the combustion chamber, and the nozzle Fis directed upward through 4the bottom wall 0f the combustion chamber,and

the nozzle .G is .directed downward through the top wall of thecombustion chamber. And allare so directed that the blasts therefromwill impinge against, and .therefore inlet to the outlet whensaid streamis delected by the supplemental streams which;

are blown into the combustion chamber through-those nozzles. lit will benoted that the main stream offuel and air as it enters the combustionchamber, is met by aproperly graduated blast from. the nozzle whichdeflectsl diagonally .'downward.'l v Be-- .fore it reaches the vbottomof the combustion chamber itis interceptedV by another prop erlygraduated'blast from nozzlel E which deflects it horizontally before thefuel particles have contacted with the bottom of the chamber; andshortly thereafter it is again intercepted bya blast from the nozzle l?by which itis deflected diagonally upward; and linally it is met by ablast of air from nozzle F by which the flaming main stream is delecteddiagonally'downward and toward the outlet in which ordinarily therepwillbe sulii- Vcient draftto carrythe products bf combus-` tion through it.By way of illustration, it

may be observed that' if the heat required inl the combustion chamberVcalls .for the combustion of only a relatively small quantity of fuel,the rate .at whchthe main stream will be blown into the combustionchamber will be correspondingly reduced. lt might, therefore,- bepossible to deect the amlng mainstream to an extent Vsulicient Ato burnall of this 'fuel by usin two nozzles, for eX- ample, nozzles D'and Thefirst one w1ll deflect the, stream downward; the nozzle E may turn thestream horizontally; andthe draft usually presented to the outletopening may be suficientto carry the flaming stream upward and throughsaid outlet.

In the construction shown in Fig. 2 there are four nozzles E', E2, F,and Gr,`wh1ch pass through the side walls ofthe combustion chamber. Theblasts blown through these nozzles successively encounter the flamingmain stream of fuel and air and de' `fleet. it and prevent it fromimpingmg against the walls of the combustionchamber,`and cause it tofollow the horizontally. sinuous path vindicated by thedotted line as ittravels through the combustion chamber from the inlet to the outletthereof. As to. this .apparatus shown in Fig. 2, it may 'be assumed thatthe so-called combustion cham-v berV is a furnace, the Hoor of which isJthe furnace. hearth. Y The flaming main stream, g

agonally into the combustion chamber from bypassing Asinuously back andforth over straight stream.

ln the constructlon shown '1n Fig. 3, the

' impinged against.

naoaoae combustion chamberA may be cylindrical or rectangular.A.v,supplemental air 'blast nozzle H is disposed directly opposite theinlet opening B. lf the chamber is cylindrical the ,outlet C may be anannular opening around the blast nozzle H. The air 'blast from nozzle Hwill, in that event, meet the main stream of air and fuel, head on, soto'say, and turn it outward and backward uponitself. l'llhe draft of theoutlet may be vsudicient to again turn this stream outward `and backwardtoward' and throughthe outlet; .or an annular series of blast nozzles Kvmay be disposed at the inlet end of said 'i chamber in such wise thatthe air blast therefrom will turn thedaming main stream back toward theoutlet.

lThe three forms of combustion chamber.

and associated means for discharging the stream of fuel and air into thesame and for discharging into it also the` necessary de,

fleeting supplemental streams, Ihave been shown as typical apparatus forpracticing the. invention; and for the purpose of emphasizing the. factthat the apparatus may 'be wldely varied, and must be varied inaccordance with the special functions tobe performed by the practice ofthe process.

The diliiculties which have heretofore' been encountered in the attemptto successfully use powdered coal as .fuel have been' stream,`fpromotethe settling of the fuel out of the stream, and necessarily cause theimpingement of the fuel particles against said bames and furnace walls,which causes more or less rapid deterioration of the 'surfaces ln manycases the use of very long combustion chambers is not practical; andeven when it `can be used there is dilliculty in getting the air andfuel so completely mixed that all of the fuel will vbe burned. In anyevent the operator has,

heretofore, had no. substantialcontrol over the flame or the heatproduced thereby. lln my invention, however all of these and otherdiculties which need Anot be catalogued, are substantially obviated. Forexample,the air streams which are blown dithe nozzles shown in thedrawing, for the primary purpose of deflecting `the aming main stream of.fuel and air, will add air to this main stream. Therefore, the4 mainstream may contain considerably less, air than is required to effectthe. complete combustion of the fuel introduced. Not only will thedeflecting air stream supply the supplemental air required, but theywill promote the more complete mixture of the fuel with the air, andtherefore, the more complete combustion of the fuel.l Additionally, itis not necessary that the main stream of fueland air shall contain allof the fuel to be burned. In case it does not, any one or more of thedeflecting streams discharged from the inclined nozzles may be made uppartly of fuel and partly of air. These streams may be made to ljoin theair stream lat any desired point, and therefore cause more uniformdistribution of the heat in different parts of the combustion chamber.Again it may be desirable that some one or more of these deectingstreams shall be neither air nor a mixture of air and fuel. For example,if in order to produce the desired deflections of the main stream theamount of air supplied in the supplemental streams delivered from thenozzles be greater than is required for the combustion of fuel, one ormore of said deiiecting streams may comprise a gas which either containsno oxygen, or a smaller percentage ofoxygen than air. Such gas might,for example, be

drawn from the stack into which the prodv ucts of combustion aredischarged. Again it might be desired to maintain a reducing iamethroughout some part of the main stream travel, and to have a reducingatmosphere in contact with the material being heated, as in some classesof metallurgical processes, and at the same time to prevent fuel or ashbeing deposited. Some one or more of the nozzles therefore may be madeto discharge such a reducing gas in the com bustion chamber.

From the foregoing it is apparent that an operator by intelligentlycontrolling the volume of the main and supplemental streams,theproportion of fuel and air therein, and the force of said streams,may burn in a small combustion 'chamber powdered coal in any desiredquantity, andl may control the iame and its heating effects in anymannery and to whatever extent desired. Likewise the deflecting streamsmay be of such character that they will in a very large degree preventthe settling of the fuel particles out of the main stream, wherefore asa corol1ary,.it will not be necessary that the' fuel be as fine as hasheretofore been necessary. It will, therefore, be seen that tosuccessfully carry on this process for produc# ing different specificresults one may, While still employing the fundamental essentials of theprocess, vary it by varying the posi'-v tions of the nozzles, by varying'their size or number, by supplying part of the air and part of the fuelthrough these nozzles, or by causing one or more ofthe supplemental saidstream as an entirety as it is passingA through'said combustion chambersolely by blowing a number of -streams of gas into said combustionchamber in different directions but against and vtransversely of saidmain stream and with such force, as will cause said main stream as anentirety to be deiected and to follow a sinuous path between the inletand outlet passages of said combustion chamber. i

2. The process of burning powdered coal,

gas or oil in a combustion chamber having inlet and outlet passages,which consists in forcefully blowing through said inlet passage lintosaid combustion chamber amain stream composed of-a mixture of fuel andair, in ignting said fuel stream, andinalso blowing a suitable number ofother streams of gasinto said combustion chamber against said mainstream, and in such vdifferent directions and with such force as willprevent the impingement of said main stream against those walls -of saidcombustion ehamber'toward which it flowed and said gas streams actingalone to cause said main stream to flow in a sinuous path between theinletand outlet passages of said chamber.

3. vThe described process. of burning powdered coal or other suspendedfuel in a combustion chamber having inlet and out'- let passages, whichconsists in forcefully blowing into said combustion chamber through saidinlet passage a main stream comprising a mixture of the fuel and avolume of air insuicient to produeejcomplete combustion of said fuel, inignting said fuel stream, and in also blowing into said combustionchamber and against said main stream a suitable number of other coursein said combustion chamber and will4 supply to said main stream suchadditional' air as may be required to promote substantially completecombustion ofthe fuel.

4. The described 1 process of burning powdered coal or other .suspendedfuelin a combustion .chamber having inlet and outlet passages, whichconsists in forcefully v blowing into.r said combustion i chamberthrough the mlet passage al man1 stream comprising a mixture of fuel'and air, in

igniting said fuel stream, and in alsoblowing into ,said conbustionchamber and against said main stream a suitable number of other streamsof 'airy-one of which contains also a quantity of fuel,-at such pointsand in such .different directions and with such force as Will vcausethem 0to mix with the main stream and be the sole means of deflecting itbodily and.y thereby Cause it to mechas follow a sinuous course throughsaid combustion chamber from the inlet to the outlet passages thereof. l

ln testimony. whereof, I hereunto aix Witnesses.

EDWARD P. ROBERTS. Witnesses:

E. L. THURsToN, M. M. ROYAN.

my signature in the presence of two 1Q

